sinβ-sinα=2sin(β-α)/2*cos(β+α)/2
0<(β+α)/指虚2<π/2
0
sin(β-α)/2>(β-α)/2
sinβ-sinα=2sin(β-α)/2*cos(β+α)/2
>2sin(β-α)/2
>2(β-α)/唯庆燃2=β-α
sinβ-sinα=2sin(β-α)/2*cos(β+α)/2
0<(β+α)/亩埋2<迅纤蚂π/2
0
sin(β-α)/竖培2>(β-α)/2
sinβ-sinα=2sin(β-α)/2*cos(β+α)/2
>